docs: def scrub(self):
          """
          The XML file seems to have mixed-encoding;
          we scrub out the control characters
          from the file for processing.
  
          i.e.?i
          omia.xml:1555328.28: PCDATA invalid Char value 2
          <field name="journal">Bulletin et Memoires de la Societe Centrale de Medic
  
          :return:
  
          """
  
          LOG.info("Scrubbing out the nasty characters that break our parser.")
  
          myfile = '/'.join((self.rawdir, self.files['data']['file']))
          tmpfile = '/'.join((self.rawdir, self.files['data']['file']+'.tmp.gz'))
          tmp = gzip.open(tmpfile, 'wb')
          du = DipperUtil()
          with gzip.open(myfile, 'rb') as fh:
              filereader = io.TextIOWrapper(fh, newline="")
              for line in filereader:
                  line = du.remove_control_characters(line) + '\n'
                  tmp.write(line.encode('utf-8'))
          tmp.close()
          # TEC I do not like this at all. original data must be preserved as is.
          # also may be heavy handed as chars which do not break the parser
          # are stripped as well (i.e. tabs and newlines)
          # move the temp file
          LOG.info("Replacing the original data with the scrubbed file.")
          shutil.move(tmpfile, myfile)
          return